Train describer system



Dec. 26, 1939. R. M. PHINNEY TRAIN DESCRIBER SYSTEM Filed Nov. 19, 1936 7 Sheets-Sheet l mtzu u v 52% m i a am w 5 S um Qm 5 uz em 5 E b a3 35 +L6+n ATTORNEY 1939- R. M. PHlN NEY TRAIN'DESCRIBER SYSTEM Filed Nov. 19, 1936 7 Sheets-Sheet 2' Dec. 26, 1939. R. M. PHINNEY TRAIN DESCRIBER SYSTEM Filed Nov. 19, v1 936 7 Sheets-Sheet 3 nan i n .manqmdw 2.53 6 9.232 wvou v m q 3 mm m u IL m8 3K3 th s .650 EL 5 mum m x E WH Dec. 26, 1939.

R. PHINNEY TRAIN DESCRIBER SYSTEM Filed Nov. 19, 1936 7 Sheets-Sheet 4 Lmtuuom 2,30

Patented Dec. 26, 1939 TRAIN DESCRIBER SYSTEM Robert M. Phinney, Rochester, N. Y., assignor to General Railway Signal Company, Rochester,

Application November 19, 1936, Serial No. 111,671

17 Claims.

This invention relates to apparatus and circuits for so called train describer systems, in which distinctive indications of the destination or other identification of approaching trains are displayed 5' at a tower or other location for the information of an operator, or for other purposes.

The present disclosure shows the invention applied to a train describer system of the so called entrance-exit, or NX route, type interlocking system, such as disclosed in the prior application of at each of the route determining points and completion or exit buttons for each of the points to which traffic may go.

In other words, for each signal location there is an entrance button,

which button requires th e cooperation of an exit ting indications relating traversing the route.

to the classes of trains An important feature of the present invention relates to the cooperation of thecircuits controlled by the auxiliary train describer exit buttons in sucha way that tion for the completion effective to not only complete the desired route a single manual operaof a particuar route is but also to transmit indications relating to the destination or identificaion of trains traversing the route.

For convenience in illustrating and describing the operation of the system of the present invention it will be assumed that the NX interlocking system is applied to an interlocking plant at each end of a large bridge, over which a large number of trains are routed in both directions.

It will also be assumed that train identification or designations are transmitted both ways over a single line circuit for identifying at each end of the bridge a comparatively proaching trains;- It is assumed that the large number of ap-.

NX interlocking systenr disclosed in the above mentioned Wight application Ser. No. 69,905, is used at the plants at each end of the bridge and, in accordance with the present invention, a regular completion button is provided for completing traffic-over the bridge when certain trains arenot to be identified, this regular button being used for train moves that either do not cross the bridge or are not to be announced at the other side. The auxiliary-completion buttons are provided to designate or classify each of a comparatively large number of trains when the last route before entering the bridge is completed, these auxiliary buttons furthermore serving to complete the NX route in the same'manner as if the regular NX button were operated. v The present invention is applied to a simplex type system, with train identifications being transmitted both ways over a single line circuit betweenthe plants at each end of the bridge, but transmission being effective only one way during a single cycleof operations of the system. The communicating apparatus which controls the transmission is started as soon as the entering block located at the entrance to the bridge is occupied, providing that there is a code setup by the auxiliary exit buttons. If a message is being transmittedin the opposite direction at this time the transmission of the message above mentioned will be delayed until the next cycle. The messages are received at the leaving block of the a separate group of storage relays for each train to be indicated. I

For convenience in describing the operation of the present invention it will be assumed that indications for 10 trains are to be stored in the order in which they enter the bridge and that the classes or designations of the first three trains are indicated by lighting a separate or individual lamp corresponding to the class of each train, as stored in each group of storage relays. It is also proposed to light a single lamp for each of the. other seven trains which may be simultaneously traversing the route between the two ends of the bridge, by lighting asingle lamp for each train irrespective of its class instead of a particular lamp to characterize the class of the train. In other words, the indication for the first three approaching trains will be selected and displayed to identify these three trains, while the indications for the seven remaining trains will show up as one light per train to indicate that there is a train of some kind'approaching.

.:When the train representedzby thefirst indicabridge and stored on storage relays, there being i tion arrives at the leaving end of the bridge and enters a particular block, the indication for the first train is extinguished and the indications for the following trains are transferred in the storage relay groups, so that atall times the lamp indicators will show in detail the classification for the first three trains to arrive at the leaving end of the bridge and as many more indications as there are trains arriving.

Other objects, purposes and characteristic features of the present invention will be in part obvipointed out as the description thereof. progresses.

In describing the invention in detail reference will be made to the accompanying drawings, in which like reference characters designate the same or similar parts in the several views and in which like letters designate similar .iunctions, with the preceding numerals associated with these reference characters representing the inclusion of such devices within a particular group. Exponent hasbeen applied to those devices located at the distant or receiving end of the bridge, it being assumed for purposes of description that transmission takes place from one end, conveniently referred to as the entering end, to the other end, conveniently referred to as the leaving end of the bridge.

Figs. 1, 1A, 2, 2A, 2B, 2C and 2D should be placed end to end, in the order named, with corresponding lines in alinement for conveniently following the operation of the system. It will be assumed that the transmitting end is at the location illustrated in Figs. 1 and 1A and that this location is connected by line wir'es iL and 2L to the receiving apparatus at the distant location illustrated in Figs. 2, 2A, 2B, 2C and 2D.

It will be understood that receiving apparatus similar to that illustrated at the receiving station, will be provided at the sending station and connected to the buses illustrated in the lower right hand portion of Fig. 1A,.this receiving apparatus being responsive to codes transmitted from the distant end in exactly the same manner as will be described in connection with the receiving apparatus illustrated in Figs. 2 to 2D inclusive. Therefore, the receiving apparatus at the entering end has been omitted for the sake of simplifying the drawings. Likewise, the same transmitting apparatus and circuits illustrated in Figs. 1 and 1A are assumed to be provided at the distantlocation and connected to the buses illustrated in Fig. 2 so indicated.

Apparatus at sending locaiion.--At the sending location, assumed tov be that illustrated in. Figs. 1 and 1A, the regular completion or exit button XB is illustrated, which button corresponds to any one of the exit buttons illustrated in the above mentioned Wight application Ser. No. 69,905, and being effective to start the NX completion operation in exactly the same manner as described in this prior application.

Associated with button XB are 15 auxiliary buttons indicated by reference letters CB preceded by a numeral or numerals, which indicates the code which the associated button causes to be transmitted over the line circuit. the top button'indicated iZMCB means that the actuation of this button causes a coded impulse to be applied to the line circuit at all four or" the steps of the operating cycle, which cycle is efiected in response to the operation of any of the amiliary buttons. The operation of the lowermost auxiliary button lCB causes a coded impulseto be applied at step 4 of such a cycle.

For example,

Other buttons cause corresponding coded impulses to be applied at the steps indicated by the preceding numerals.

Relays I2CC and MCC are code combination relays operated in response to the actuation of the buttons to which they are connected, relay IZCC when picked up eiTecting the energization of code storage relays ICS and 20S and relay SiCC when picked up effecting the energization of code storage relays 3CS and 4C8. These code I storage relays, ECS and fiCS inclusive, are also ous from the accompanying drawings and in part energized by the actuation of certain of the push buttons.

Relay T is the track relay associated with the entering block at the entering end of the bridge and relay TS is a track stick relay controlled by track relay T under certain conditions, as will be pointed out in detail. Code storage r peating relay CSP repeats the operation of any of the code storing relays, but is not energized until both of the code combination relays are deenergized in response to the release or restoration of any code button which has been actuated.

A guard lamp or hands off lamp GL is lighted to indicate that it is useless to attempt to set up a designation on the code buttons. An attempt to set up a combination on these code buttons when lamp GL is lighted is ineffective. Emergency start button ESB is provided for starting the system into operation when there is no train present. Such an emergency start may be ccnveniently used for test purposes and the like. Cancellation button CNB is for the purpose of cancelling a designation set up on the storage relays to correct an error in setting up a t identification. The buzze illustrated in t lower right hand portion of Fig. l and buzzer relay BZ illustrated in Fig. 1A, are for the purpose of calling the operators attention to an incomplete cycle, which may be due to some unstandard condition. Relay BZ will be picked up if an incomplete cycle occurs and the buzzer will be sounded to call the operators attention to this fact.

Referring to Fig. 1A, relay C is a cycle controlling relay and is picked up at the sending end for controlling the code selecting circuits. Relays PC and NC are positive and negative code sending relays respectively for applying positive or negative impulses to the line circuit, as determined by the code to be transmitted at each step of a cycle. Relay F is a polar, biased to neutral line relay and is for the purpose of repeating the polarity of the impulses applied to the line circuit. Relay FA repeats the operations of relay F and is for the purpose of controlling the step ping relay bank. Relays SA and SB are of the slow releasing type and are for the purpose of defining the bounds of an operating cycle, these relays being picked up in sequence at the beginning of a cycle and dropped out in sequence at the end of the cycle.

A stepping relay bank is provided comprising half-step relay VP and stepping relays EV, 2V, 3V and 4V. These stepping relays step through a cycle in response to a series of impulses applied to the line circuit and select local channel circuits at each step. Executing relay EX is picked up in response to the last impulse applied to the line and is for the purpose of executing the conditions set up on the decoding relays at the receiving end, by selectively operating the train designation storage relays in accordance with the code decoded by the decoding relays. Relay EX performs other detailed functions which will be pointed out in the detailed description.

Lockout relay L is for the purpose of determining the location from which transmission takes place, this relay being picked up at the receiving location and remaining down at the sending location. The picking up of the lockout relay at the receiving location disables the code sending circuits and renders the executing bus for the code receiving circuits effective. Re-

sistance RS is inserted in the line in place of the upper winding of relay L0 for the purpose of maintaining the line circuit resistance uniform after the upper winding of relay LO has been disconnected from the line.

Apparatus. at receiving location.The apparatus at the receivinglocation comprises a bank of stepping relays. including half-step relay VP and stepping relays [V 2V 3V and 4V which bank of stepping relays operate in synchronism with the stepping relays at'the sending end. In other words, during sending or receiving operations the stepping relays at both locations operate through the cycle in synchronism. Executing relay EX corresponds to relay EX of Fig. 1A. Lockout relay LO corresponds to lockout relay LO illus-- trated in Fig. 1A.

Line relay F and repeater relays FA SA and SB correspond to relays F, FA, SA and SB of Fig. 1A. Code sending relays PC and NC correspond to relays PC and NC of Fig. 1A. Cycle determining relay C corresponds to relay 0 of Fig. 1A. Buzzer relay BZ corresponds to relay BZ of Fig. 1A. .Referring to Fig. 2A, the code receiving or decoding relays comprise relays lPS ZPS SPS and 4198 which relays are picked up or not at the four steps of a cycle as determined by whether or not the impulse at each step is a impulse. Repeating relay PSP associated with the code receiver group is for the purpose of disconnecting the pickup circuits of the decoding relays under certain conditions, as will be later pointed out.

Referring to Figs. 2A, 2B and 20, ten banks of train designation storage relays are p-rovided,each bank comprising four relays which are picked up in accordance with the particular decoding relays picked up when the transfer is made from the decoding relays to the designation storage relays. This transfer is effected by means of the excuting circuit when the communicating apparatus has completed its four steps and the message has been stored in the decoding relays. The four relays for the train designation storage groups No. 10, No. 2 and No. l have been shown, while the four conductors leading to these relays for the other seven groups have only been indicated and the relays for these other seven groups omitted.

The groups of train designation storage relays have an associated transfer relay IR to IDR inelusive and each of these transfer relays controls and it will be understood that the train desig-- nation storage relays of groups 1 and 3 also con- 75 trol. similar groups of indicatorlamps by means of similar circuits, which circuits are not shown for the sake of simplicity in the drawing. It

will also be understood that, in the event that it is desired to indicate the class of more than three approaching trains, then additional groups of indicator lamps may be connected to additional train designation storage relays as required.

A lamp indicated train No. 10 is shown controlled by the train designation storage relays of group No. 10, which lamp when lighted indicates that a tenth train is approaching, it not being required to indicate the class of this train. It will be understood that similar lamps are controlled by the No. 9, the No. 8, the No. 7, the No. 6, the No. 5 and the No. 4 train designation storage relay groups, for indicating the number of trains approaching, in addition to those which are identified by the train identification lamps associated with the first three groups.

Track relay T (see Fig. 2C) is associated with the leaving block and, by means of its repeater relays TPA, TPB and TPC, the clearing out and transfer operations of the train designations stored are effected.

Relay WPP is illustrated as controlled by switch machine lever SML this relay controlling extension circuits to an extension receiver illustrated in the right hand portion of Fig. 2C and in Fig. 2D. With relay WPP in its normal position, as indicated, the first three indications on the train designation storage relays are transferred to another arrival point and registered on train designation storage extension relay groups 3A, 2A and IA. These extension relay groups comprise train designation storage relays similar to those previously referred to and comprise transfer relays AIR, A2R, MR and their associated repeater relays AIRP, A2RP and A3RP, which function in a manner similar to corresponding relays associated with the groups of train designation storage relays. It will be understood, as indicated by the note associated with the back contacts of relay WPP that the circuits connected to these contacts may lead to B extension storage groups for transferring train identities to a second arrival point when relay WPP is deenergized by lever SML in its reverse position.

Relay T of Fig. 2D is associated with the block at the extension arrival point, this track relay controlling repeater relays ATPB and ATPC for purposes which will be later described. Emergencysuppression buttons ESB and ESB and emergency clearing buttons ECB and ECB are associated with the clearing sections illustrated'in Figs. 20 and 2D and are for the purpose of bringing the system into step with the trains, in the event of the systems getting out of step. These buttons are also provided for testand maintenance purposes.

Although the present disclosure and the description relates only to the transmission from the entering block to the leaving block, it will be understood that the circuits and apparatus, including thetransmitting and receiving equip ment at both'ends, are substantially the same so that train designations may be transmitted either way over'the line. The direction of transmission is determined by the conditions of the C and LO relays, the LO- relays effecting the looking out of the apparatus in the event that an attempt is made to transmit both ways at the same time, this lockout feature being described later.

It s panama th ha a te t ea u s of the present invention will be best understood by further description being given from the standpoint of operation.

OPERATION Setting" up a route.-Since the train identification feature of the present invention is applied to the exit end of a route, for example, a route ccmpleted by the operation of button RB of 11 Fig. 1 or the operation of some one of the i5 auxiliary completion buttons, and since the com- ,pletion of the setting up of a route in the so called NX type system is fully illustrated in the above mentioned prior application Ser No. 69,905, it is believed unnecessary to point out the operations relating to the completion of such a route, except to mention that the closure of the contact by the operation of button XE applies energy ,to the NX start wire, which is effective to com- :plete the setting up of the desired route. Of course the operation of button XB completes the setting up of the route without the transmission of any sort of train identification.

When the route is completed by operating some one of the auxiliary buttons, then one or more of the code storage relays ICS to ACS inclusive will be picked up and energy is applied to the NX start Wire over a circuit extending through back contact Ii! of relay CSP and some one of front contacts ll, l2, l3 or M of relays lCS to QCS inclusive, to the NX start conductor. Since it only requires a momentary energization of the NX start conductor, this circuit is opened when relay CSP is picked up following the picking up of one or more of the code storage relays, as will be later described.

Registration of train identities.-Considering the function of registering train identity by the operation of one of the auxiliary completion buttons illustrated in the left hand portion of Fig. 1, it is contemplated that each of 15 trains will have a particular code designation. These code designations may be of any form desired such as letters or numerals, but for convenience in describing the operation of the system, the 15 auxiliary buttons are given reference numerals preceding the reference characters CB, which refer to the code transmitted. For example, the top button is designated HEMCB, which indicates that a code impulse is transmitted at each of the four steps of an operating cycle for picking up four decoding relays at the receiving end. The third button from the top is designated l2 iCB, which indicates that a coded impulse is transmitted to the receiving end for picking up decoding relays 5, 2 and t at the first, second and fourth steps of the operating cycle. For convenience in describing the operation of the system, it will be assumed that button [240B is actuated to complete the setting up of a route through the interlocking plant.

The operation of button 124GB closes a circuit for picking up relay lZCC which extends from front contact 30 of relay T,'back contact 2 of relay CSP, right hand contact of button lZ iCB and winding of relay I2CC, to Another circuit extends through the left hand contact of button IZQ-CB and the winding of relay 408 for picking up this relay. Relay 40S closes a stick circuit for itself which extends from back contact [6 of relay EX (Fig. 1A), conductor ll, normally closed contact of button CNB, front contact l8 and winding of relay 4C8, to

The pickingup of relay l2CC closes obvious circuits for picking up relays ICS and ZCS at .front contacts l9'and 2n. Relays Ice and s close stick circuits for themselves at their front contacts 2! and 22 to over the previously.

described circuit including back contact 16 of relay EX.

Vfhen button I24 is released, relay |2CC is deenergized and a circuit is closed for picking up relay CSP which extends from front contact 23 of relay T, front contact 24 of relay 4CS (also front contacts 25 and 26 of relays ICS and ZCS in multiple) winding of relay 05?, back contacts 27 and 28 of relays MCC and 120C re spectively, to Relay CSP completes a stick circuit for itself at front contact l5, which is independent of front contact 23 of relay T. The opening of back contact 2 of relay CSP removes energy from the auxiliary push buttons, so that an operation of any one of these buttons during the time that the guard lamp GL is lighted will be ineffective. Lamp GL is energized over a circuit closed at front contact 29 of relay CSP and at back contact 39 of relay T, this latter contact lighting lamp GL as long as the entering block is occupied to indicate to the operator that it is useless to actuate a code button.

From the above example it is believed obvious how other combinations of the code storing relays are energized in response to the operation of the dinerent code buttons. Code combination relay MCC is picked up in the event that either one of buttons EZSQCB, 133GB, 236013 or 3 2GB is actuated and this relay in turn closes circuits at its front contacts 3| and 32 for picking up relays ECS and -iCS. Relay IZCC is energized when code buttons lZS SCB, l23CB, EZ SCB or IZCB are operated. It will be understood that the purpose of relays I ZCC and 3400 is to reduce the number of push button contacts re quired to set up all of the necessary combinations on the code storage relays.

Cycle of stepper operations-After the code combination has been stored as above described, it remains stored on the storage relays until the corresponding train enters the entering block, at which time relay T is dropped and relay TS is picked up over a circuit extending from back contact 23 of relay T, front contact 33 of relay CSP and winding of relay TS, to Relay TS closes a stick circuit for itself at its front contact 3 1 which is independent of back contact 23 of relay T.

Cycle determining relay C is now picked up over a circuit extending from front contact it! of relay CSP, front contact 35 of relay TS, conductor 36, back contact 31 of relay BZ, back contact 38 of relay LO, back contact 39 of relay SA and Winding of relay C, to

It might be well to mention at this time that the system can be started through a cycle of operations by the operation of emergency start button ESB, which completes the above described circuit at the contact of this button instead of front contact 35 of relay TS. Such an emergency start condition is desirable to operate the system when there is no train present for test and emergency purposes.

Relay PC is now picked up over a circuit extending from front contact &0 of relay C,

back contact H of relay LO, back contacts 42,,

(i3, 44, 45 and 46 of relays VP, 4V, 3V, 2V and IV respectively and winding of relay PC, to

The picking up of relay PC energizes the line circuit with a positive impulse which will be conveniently referred to as a conditioning impulse, since it conditions the apparatus at both 65 of relay SB. It will be pointed out'at this tact 49 of relay BZ, winding of relay F, line conductor 2L, winding of relay F back contact I00 of relay B2 back contact IIlI of relay NC back contact I52 of relay PC upper winding of lockout relay L0 back contact I03 of relay SB back contact I54 of relay PC back contact I05 of relay NC line conductor IL,back contact 5E] of relay NC and front contact 5| of relay PC, to the terminal of battery LB.

The positive energization of the line circuit positions line relays F and F to the right and picks up lockout relay L0 Relay FA is now picked up over a circuit closed at contact 52 of relay F in its right hand dotted position. It will be pointed out at this time that, during the intermittent operation of relay F during the following cycle, relay FA is intermittently operated by contact 52 in either its right or left hand positions. In other words, relay FA is a direct repeater of relay F. Relay SA is picked up over a circuit closed at front contact'53 of relay FA, relay SB is picked up over a circuit closed at front contact 54 of relay SA and these two relays remain up during the'intermittent operations of relay FA during the cycle.

A similar series of operations takes place at the distant location illustrated in Fig. 2, by relay F energizing and deenergizing relay FA at contact I06. Relay SA is energized by the closure of front'contact III! of relay FA and relay SB is energized by the closure of front contact I08 of relay SA The picking up of relay SB closes a stick circuit for relay LO includingfront contacts I09 and IIU'of' these two relays. It will be understood that relay FA follows the intermittent operations of relay F during the cycle.

Referring back to Fig. 1A, relay VP is now picked up over a circuit extending from front contact 55 of relay SB, front contact 56 of relay FA, back contact ill of relay IV and winding of relay VP, to Relay VP closes a first stick circuit for itself at its front contact 58, which is independent of front contact 56' of relay FA. The picking up of relay VP opens the above described circuit for relay PC at back contact 42, so that relay PC drops and deenergizes the line to mark the end of the conditioning period.

In response to the deenergization of the line, relays F, F FA and FA are dropped and a second stick circuit is closed for relay VP extending from front contact 55 of relay SB,

Winding of relay VP, to

Relay IV is now picked up over a circuit extending from front contact 55 of relay SB,

back contactfifiof relay FA, front contact'GI of relay VP, back contactliZ of relay 4V, back contact 63 of relay 2V and winding of relay IV, to Relay IV closes a stick circuit for itself at its front contact 64 to at front contact time that relays 2V, 3V, 4V and EX, which are operated during additional steps of the cycle,

close similar stick circuits for themselves at" front contacts 66, 61, 68 and 59.

The picking up of relay IV completes the first recalled that relay ICS is picked up, so that this -lay PC, to

first codeselecting circuit extends from (1-),

front contact 40 of relay 0, backcontact' ll of relay'LO, front contact 42 of relay VP, back contacts 'IIlfiII and I2 of relays-4V, 3V and 2V, front contact I3 of relay IV, conductor I4, front contact 15 of relay ICS, conductor Hi and winding of re- The picking up of relay PC again energizesjthe line with a positive impulse over the previously described circuit and relays F and F areactuated to the right and relays l=-'A and FA are picked up.

The 'pickingupof relay FA deenergizes relay VP, because its first stick circuit is open" at back contact 5? of relay. IV and its second stick circult is openedat back contact 56. of.relay FA. The dropping of relay VP opens'the above d scribed circuit for relay PC atfront contact 42.

Relayj'PC drops, deenergizes the line and relays F, FA, F and'FA are deenergized. Relay is now picked up over a circuit extending from 7 front contact 55 of relay SB, back contact relay 2V, to "The picking up of relay 2V completes the second code'selecting circuit and since relay 203 is picked up, this code selecting tact 42 of relay VP, back contact 43 of 'relay 4V, back contact 44 of relay 3V, front contact45 of relay 2V, conductor 8|], front contact 8I of relay ZCS, conductor I6 and winding of relay PC,'to'( 4 g a The picking up, of relaylPCagain applies a positive impulsetotheJIine for positioning relays F and F to theright and for picking up relays FA and FM. Relay VP is now picked up over acircuit extending from front contact 55 of relay SB, front contact 56 of relay FA, back contact 82 of relay 3V, front contact 83' of @relayZV and'win'ding of relay VP, to(-.)

' The picking up of relay VP drops relay PC because of open back contact 42 and the dropping circuit efiectsthe picking up of relay PC overa circuit extending from front contact 40 of relay C, back contact M of relay LO, back conof relay PC deenergizes theline, which in turn lay VP,,back contact 62 of relay 4V, front conjefiectsthe dropping of relays F, FA, F and F Relay 3V is'now'picked up. over a circuitextending' from front'cont'act 5510f relay SB, back contact 69 offlrelayFAj, front contactflil of .re-

The picking .upmf relay 3V "selects the third 7 code to be applied-to the line and since relay 3CSis down, this will be a negative code due to relay NC being picked up over a circuit extending from front contact 40 of relay C, back contact 4I of reIa'yQLO, front contact 42 of relay VP, back contact'lllof relay 4V, front contact 'II of relay'3V, conducto-r'84, back contact 85 of relay 30S, conductor 86an'd winding of relayfNC, to With' relay NC up and relay PC down,

pole changing contacts 48, v50, 41' and 5| a'rel eifectiveto reverse'the connection of batteries" LB to the line from that previously described in polar contacts of relays F and F to the left and relays FA and FA are picked up.

Relay VP is no vv dropped because its first stick [energized because the atove described circuit in 75 v cluding conductor 84 is open at front contact 42 of relay VP.

The dropping of relay NC deenergizes the line circuit andrelays F, F FA and FA are dropped. Relay AV is now picked up over a circuit extending from front contact 55 of relay SB, back contact Gil of relay FA, back contact SI of relay 'VP, back contact I? of relay EX, front contact '18 of relay 3V and winding of relay 1V, to

'The picking up of relay 4V makes the fourth code selection and since relay 40S is picked up, relay PC is picked up over a circuit extending from front contact 40 of relay C, back contact 4| of relay LO, back contact 42 of relay VP,

front contact '43 of relay 4V, conductor 8'I, front contact 88 of relay 40s, conductor 76 and winding of relay PC, to The picking up of relay PC appliesa positive impulse to the line circuit for positioning relays F and. F to the right and for picking up relays FA and FA Relay VP is now picked up over a circuit extending from front contact of relay SB,

"front contact 56 of relay FA, back contact 89 of relay EX, front contact 90 of relay 4V and winding of relay VP, to The first and second 'stick' circuits for relay VP are completed as prei viously described.

The picking up of relay VP opens the above described circuit for relay PC at back contact 42, so that relay PC drops and deenergizes the line circuit and relays F, F FA and FA are dropped.

Relay EX is now picked up over a circuit extending from front contact 55 of relay SB,

back contact 68 of relay FA, front contact 6| of relay VP, front contact 62 of relay W and winding of relay EX, to Since relay EX selects no circuit for'picking up either relay PC or NC,

these two relays remain down and the line remains deenergized for a sufficiently long period "of time to effect the dropping of relay SA, be-

cause of open front contact 53 and the dropping of relay SB because of open front contact 5d.

The code storage relays are now deenergized because their stick circuit is open at back contact I6 of relay EX and'at front contact 9| of relay 'SA, which front contact was closed at the be- "ginning of the cycle for applying to the stick circuit for the code storage relays by way of conductor 92. The dropping'of the code storage relays'elfects the release of relay CSP because all of the contacts 24', 25, 2E and 96 are open. Relay TS drops because of open. front contact 33 of relay CSP and relay C is dropped because its stick circuit is open at front contact of relay SB and contact 94 of relay F, which stick circuit includes front contact 93 of relay C and was completed at the beginning of the cycle. stepping relays IV to 4V inclusive and relay EX are now deenergizedbecause of open front conby dotted line IM and these stepping relays,

as well as relays SA and SB-, aredropped out in the same manner describedin connection with the operation of Fig. 1A.-

When the train leaves the entering block, re-

;' lay T is picked up and lamp GL is extinguished as an indication to the operator that the next code canbe set up for transmission. It will be understood that the designations for additional "impulse because this impulse is positive. I circuit for energizing relay 4PS is the same as Relay VP,

trains are setup and transmitted to the distant end; in a manner similar to that described in connection with the designation corresponding Fig. 1A and stepper of Fig. 2 are operated through a cycle, the code stored on the code storage relays of Fig. l is transferred to the code receiving relays of Fig. 2A, comprising relays IPS to 4PS inclusive, these code receiving relays being conditioned during the cycle in accordance with the condition of the code storage relays.

At the end of each cycle the code receiving relays are restored to normal ready for the next cycle, by deenergizing their stick circuits (including conductor I23) at open front contact I22 of relay SB For example, when code I2 3 is transmitted as above described, code receiving relays IPS 2PS and lPS are picked up. Relay IPS is picked up because the first coded impulse is positive, over a circuit which extends from contact II5 of relay F in its right-hand dotted position, front contact IIS of relay L0 back contacts H1, H8 and II9 of relays 6V 3V and 2V respectively, front contact I29 of relay IV conductor 'IZI, back contact 2% of relay PSP and upper winding of relay IPS to Relay IPS closes a stick circuit for itself extending from front contact I22 of relay SE conductor I23, front contact I2 and lower winding of relay [PS to Relay 2PS is energized because the second coded impulse is positive, over a circuit which includes contacts H5, H6, II? and H8 as before,

' but in this case it extends through front contact H9 of relay 2V conductor I25, back contact 2M of relay PSP and upper winding of relay ZPS to Relay *ZPS closes an obvious stick circuit for itself at its front contact I2fi.

Relay 3PS is not energized because the third coded impulse is negative,'causing contact I I5 of relay F to be'actuated to the left instead of to the right, when relay SPS is'selected by front contact II8 of relay 3V Relay lPS is energized by the fourth coded that previouslydescribed, except that it extends through front contact Iil' of relay 4V conductor IZ'I, back contact 293 of relay PSP and upper winding of relay iPS to Relay lPs closes an obvious stick circuit for itself at its front contact I28.

At the end of the cycle, the picking up of relay EX executes or transfers the code received by and its back contact I29 open, the picking up of relay EX and the consequent opening of its back contact I3! removes energy from delay bus for a purpose which will be later de- The scribed. At the end of the clearing-out period at the end of the cycle, the dropping of relay EX groups.

ing of relay IDS2, to

removes energy from execution bus and again applies energy to delay bus.

The energy applied'to conductor I32 is effective to pick up relays IDSI, IDS2 and IDS I.

; The circuit for picking up relay IDS extends from onconductor I32, front contact I34 of relay IPS back contact I35 of relay IOR, back contact I36 of relay QRP, back contact I31 of relay QR, back contact I38 of relay BRP, back contact I39 of relay 8R, back contact I40 of relay 1RP, back contact I4I of relay 1R, conductor I55, back contact I42 of relay 6RP, back contact I43, of relay 6R, back contact I44 of relay 5RP, back contact I45 of relay 5R, back contact I48 of relay 4RP, back contact I41 of relay 4R, back contact I48 of relay 3RP, back contact I49 of relay 3R, back contact I50 of relay 2RP, back contact I5I of relay 2R, back contact I52 of relay I RP, back contact I53 of relay IR, conductor I54 and lower winding of relay IDSI, to Relay IDSI closes a stick circuit for itself extending from back contact I56 of relay TPB, front contact I51 and upper Winding of relay IDSI, to

Relay IDS2 is picked up because relay 2PS is up, over a similar circuit extending through front contact I58 of relay 2PS and back contacts I59, I68, 58!, I62, I63, I64, I65, conductor I66, back contacts I61, I68, I69, I18, I1I, I12, I13, I14, I16, 916, I11, I'i8, conductor I16 and lower wind- Relay IDS2 closes an obvious stick circuit for itself at its front contact I80.

Relay IDS3 is not picked up because relay 3PS of the code receiver was not picked up.

Relay IDS4 is picked up because relay 4PS of the code receiver was picked up. The circuit for picking up relay IDS4 is similar to those previously described and extends through front contact I8I, back contact I82 to I88, inclusive, conductor I89, back contacts I98 to I 99, inclusive, back contacts 266 and 25I, conductor 252 and lower winding of relay IDS4, to Relay IDS4 closes an obvious stick circuit for itself at its front contact 253.

Lamp I24L is lighted over a circuit extending from front contact 2540f relay IDSI, front contact 255 of relay IDS2, back contact 256 of relay IDS3, front contact 251 of relay IDS4 and lamp 524L, to

Although not shown on the drawings, it will be understood that pyramid contacts on relays IDSI to IDS4, inclusive, are arranged in the same manner as shown in connection with the No. 2 designation storage relay group, comprising relays ZDSI to 2DS4, inclusive, for selecting any one of the fifteen indicator lamps in accordance with the code received. Likewise, a similar set of pyramid contacts (not shown) is associated with the No. 3 designation storage group of relays, so that the first three trains may be indicated by selectively energizing an indicator lamp of each of the first three designation storage It will also be understood that any number of designation storage groups of relays may be provided with indicator lamps and pyramid contacts for indicatingany number of approaching trains up to the capacity of the system.

When energy is removed from execution bus and again applied to delay bus, transfer relays IR and IRP are picked up for transferring the above described circuits, leading from the contacts of the code receiver relays, from the No. 1 designation storage group of relays to the -No."2 designation storage group of relays, in

readiness for registering the designation of the second approaching train.

Relay IR is picked up over a circuit extending from on delay bus, conductor I33, back contacts. 258 to 266, inclusive, conductor 288, back contacts 281 to 211, inclusive, conductor 219, front contact 288 of relay IDSI (or front contacts 28I, 282, 283 of any one of the other relays of the No. 1 designation storage group), conductor 284 and lower winding of relay IR, to Relay IR closes a stick circuit for itself at its front contact 218, which excludes the series circuits including the back contacts of the R and RAP-relays of the other groups. Relay IRP is picked up over a circuit closed at front contact 285 of relay IR. The picking up of relay IRP and the consequent opening of its back contact 211 opens the above described pick-up circuit for relay IR, so that this relay is now dependent upon its stick circuit for its energization.

It will now be assumed that a second train en ters the entering-block; This is effective to cause the steppers to operate through another cycle in synchronism as before, and in this case the line will be energized or not energized at the four steps of the cycle in accordance with the code transmitted, as determined by-the class of the train.

Assuming that this second train requires the energization of lamp 4L associated with the No. 2 designation storage group, it will be obvious that this requires the picking up'of relay 2DS4, which in turn requires that code receiving relay 4PS be picked up. The above combination requires a positive impulse on the fourth step only and in response to the negative impulses on the first three steps, relays IP8 2PS and 3P8 are not picked up. Relay 4PS is picked up on the fourth step in the manner previously described.

During the execution period at the end of the cycle, relays 2DSI, 2DS2 and 2DS3 are left down and relay 2DS4 is picked up. over a circuit previously described and including front contact I8I of relay 4PS the lower set of selecting back contacts on the R and RP relays, up to contact 258 ,of relay IRP and then by Way of front contact 258 and the lower winding of relay 2DS4, to Relay, 2DS4 is stuck up over a circuit extending from front contact 286 of relay IRP, front contact 281 and upper winding of relay 2DS4, to

- Lamp 4L is now lighted over a circuit extending from back contacts 288, 289 and 298 of relays ZDSI, 2DS2 and 2DS3, respectively, front contact 29I of relay 2DS4 and lamp 4L, to

At the end of the execution period for the second cycle, relay 2R is picked up over the same circuit previously described for picking up relay IR, up to back contact 216 of relay 2RP and then by way of front contact 292 of relay 2DS4 to the lower winding of relay 2R. The picking up of relay 2R closes a stick circuit for itself at its frontcontact 216 and at its front contact 298 it closes a circuit for picking up relay ZRP. The opening ofback contact 215 of relay ZRP opens the pick-up circuit for relay 2R, so that this relay is dependent on its stick circuit for its energization. I

7 Assuming that the third train to enter the entering block requires that lamp I8L (not shown) of the No. 3 storage group to be lighted, it will be obvious that this requires the picking up of relays 3DSI and 3DS3, and that relays 3DS2 and 3DS4 of this group (not shown) remain down.

Itis believed unnecessary toshowatheldesignav75 III tion storage relays of the other groups, including group No. 3, since an understanding of the operation of these groups of relays in response to succeeding codes transmitted over the line may be had by analogy to the operation of the first two groups previously explained.

The picking up of the first and third designation storage relays of the No. 3 group eiTects the lighting of lamp I3L of this group, over circuits which will be understood by considering the circuitfor lamp ISL of the No. 2 group as an example.

The transfer relays 3R and ERP are picked up after the end of the execution period of the third cycle in the same manner as described for the first and second groups. From the above examples it will be apparent how ten succeeding trains may have their classes registered on the ten desi nation storage groups of relays, in response to their codes transmitted over the line circuit during ten cycles of operations of the steppers, with the codes for registering these train classes being provided in sequence by the operation of the exit buttons, shown in the left-hand portion of Fig. 1, in different combinations.

Storage trensfc'r.The above description specifically sets forth the manner in which the first three trains to enter the entering block have their classes stored on the first three designation storage relay groups and how these relay groups selectively energize individual lamps corresponding to the classes of these first three trains. From this explanation and considering that the R and RP transfer relays are picked up in response to a designation stored on each group of storage relays, it will be apparent that additional trains, up to ten, will be stored on the storage groups numbered 3 to 10 inclusive, the No. 10 group of relays being illustrated in detail in Fig. 2A.

Any one of the designation storage relays of the No. 10 group closes a circuit at front contact 295, E95, 295 or 29'! for lighting lamp 298 as an indication that there is a tenth train in the intervening section of track and it will be obwhich are in the in ervening section of track.

In other words, lamps similar to 298 indicate that there is a train of some class approaching for each lamp which is lighted, while the indicator lamps associate-d with the first three designation storage groups of relays indicate the class of each of the first three trains approaching.

Since the first, second and third approaching trains are distinctively indicated on the first, second and third designation storage groups of lamps, it becomes necessary to transfer or step up the class indications from each higher numbered group to the next lower numbered group when a train enters the leaving block associated with the exit end of the bridge, It will now be pointed out in detail how the indication for the third train is transferred to the second group and the indication for-the second train is transferred to the first group when the first train enters the leaving block with which track relay T (Fig. 2C) is associated. From this explanation it is believed that it will be obvious how the transfer is made from any other group to the next lower numbered group in the series.

When the first train enters the leaving block, relay T is dropped and a circuit is closed at its 'back contact 240 for picking up relay TPA. Re-

lay TPA' closes a circuit at its front' contact 2 for picking'up relay TPB and relay TPB completes a circuit for picking up relay TPC, which extends from front contact 243 of relay TPB and winding of relay TPC, to

The picking up of relay TPB opens the stick circuit for the relays of the No. 1 designation storage group at back contact 556 and,in the example assumed, relays iDSI, IDS2 and iDSd, which were picked up,'are released. It will be understood that these relays release during the interval between the opening of back contact I56 of relay TPB and the closure of front contact 245 of relay TPC, which latter contact is for the purpose of applying energy to the stick circuit, so that these relays will be stuck up when picked up in response to the transfer operation.

The dropping of relay IDS I opens the above described circuit for lamp I24L and this lamp is extinguished.

Relay IR is now dropped because the circuit for its lower winding is open at open front contacts 280 to 283 inclusive and the circuit for its upper winding is open at back contact 248 of relay2R. The dropping of relay IR and the consequent opening of its front contact 285 deenergizes relay I RP which, due to its slow acting characteristics, drops after a short interval of time. i

The dropping of relay IR completes a transfer circuit for transferring the indication stored on the No. 2 group to the No. 1 group. Recalling that relay EDS; of the No. 2 group is picked up, this circuit extends from front contact 26? of relay TPC, conductor 248, front contact, 2 19 of relay 2DS4, back contact of relay IR, conductor 252 and lower winding of relay IDSd, to Relay IDS4 closes its stick circuit at front contact 253, which is completed at front contact 245 of relay TPC. With relay IDS l picked up and the other relays of this group down, the pyramid circuit is completed for lighting lamp 4L of this group, in the same manner as indicated for the lighting of lamp 3L of the No. 2 group.

The dropping of relay IRPis effectedafter the above transfer is made, due to its slow acting characteristics, and relay 2DS4 is dropped because its stick circuit is opened at front contact 286 of relay IRP and because its pick-up circuit is open at front contact 259 of relay IRP. This extinguishes lamp 1L of the second group. Relay 2R is now dropped because the circuit to its lower winding is open at front contact 292 of relay 2DS4 and the circuit to its upper winding is open at back contact 230 of relay 3R. Relay ZRP is now dropped because of open front contact 293 of relay 2R.

The dropping of relay ZDS I completes a circuit for again picking up relay IR which extends from front contact 23I of relay 2RP, back contacts 232, 233, 234 and 235 of relays ZDSI to ZDS-l inclusive, back contact 2?! of relay IRP, conductor 21 9, front contact 283 of relay IDS i,

conductor 284 and lower winding of relay IR,

to Relay IR closes a stick circuit for itself at its front contact 278, which is independent of the above described pick-up circuit including back contact 21'!- of relay IRP, which pick-up circuit will be opened by the picking up of relay IRP in response to the closure of front contact 285 of relay IR.

The picking up of relay IRP completes the circuit for effecting the transfer from the No. 3 group'to the No. 2 group and, since relays 3DSI and 2DS3, to

and SD83 of the third group (not shown) are picked up, corresponding relays ZDSI and 2DS3 of the No. 2 group will be picked up in response to the transfer operations.

Relay 2DSI is picked up over a circuit extending from front contact 236 of relay IR through the front contacts of the No. 3 designation storage relays which are picked up (assumed to be 3DSI and 3DS3 which have contacts corresponding to front contacts 23'! and 238 of relays 2DSI and 2DS3 respectively), back contacts I5I and 239 of relay 2R, front contacts I 52 and 229 of relay IRP and lower windings of relays 2DSI The picking up of these two relays of the No. 2 group complete obvious stick circuits for themselves at their front contacts 221 and 228 to at front contact 286 of relay IRP.

The picking up of relays 2DSI- and 2DS3 complete a circuit for lighting lamp- I3L which extends from front contact 288 of relay 2DSI, back contact 226 of relay 2DS2, front contact 225 of relay 2DS3, back contact 224 of relay ZDSd and lamp I3L, to This completes the transfer from the No. 3 to the No. 2 group.

The dropping of relay ZRP, as previously described, causes the dropping of relays SDSI and 3DS3 (not shown) because of open front contacts I and 223 of relay 2RP and because the stick circuit for these relays is open at a front contact of relay 2RP similar to front contact 235 of relay IRP. The dropping of these two relays of the No. 3 group extinguishes lamp I3L of this group and effects the dropping of relay 3R, because its lower winding will be open at the front contacts of the storage relays of this group, similar to contacts 220, 22!, 222 and 292 illustrated in connection with the relays of the No. 2 group. It will be understood that the upper winding of relay 3R is not energized at this time, since it re quires the energization of execution bus, including conductor I32, for energizing the winding. The dropping of relay 3R effects the dropping of relay 3RP because relay 3RP is a direct repeater of relay 3R.

Relay 2R is picked up in response to the drop- ;ping of relays 3DSI and 3DS3 (not shown), over a circuit extending from front contact 2ID of relay 3RP (this circuit being effective before the dropping of relay 3RP due to its slow acting characteristics), through back contacts of the No. 3 group of designation storage relays (similar to back contacts 232 to 235 inclusive of relays 2DSI to 2DS4 inclusive), front contact 220 of relay ZDSI (in multiple with front contact 222 of relay 2DS3) and lower winding of relay 2R, to Relay 2R effects the picking up of relay ZRP by the closure of front contact 293.

This completes the transfer from the No. 2 group to the No. 1 group and from the No. 3 group to the No. 2 group, with the storage relays of the No. 3 group being restored to normal in condition for storing the next approaching train, in a manner which will be obvious from the above description.

The transfer from one group to another cannot take place while a new message is being stored. The prevention of a transfer under this condition is due to the removal of energy from delay bus conductor I33 during the execution period, when a message is being registered on the code receiver. The opening of back contact I29 of relay L0 (effected during the receiving of relay EX (effected during the execution of a code) removes from conductor I33, which is'required for picking up a transfer relay, such as relay 2R over a circuit including conductor I33, back contacts 253 to 265 inclusive, conductor 266, back contacts 261 to 215 inclusive and one or more of the front contacts 220, 22I, 222 and 292, to the lower winding of relay 2R. By means of this arrangement the transfer operation is held off until the receiving apparatus is in a condition when no code is being executed.

Clearing out operaiion.When the first train leaves the leaving block the picking up of relay T effects the dropping of relays TPA, TPB and TPC and since back contact I56 of relay TPB is closed before front contact 245 of relay TPC is opened, energy is maintained on the stick circuits for the relays of the No. 1 designation storage group. Likewise, since back contact 2II of relay TPB is closed before front contact 241 of relay TPC is opened, energy is maintained on conductor 248, so that the transfer may be made from the No. 2 group to the No. 1 group at the instant that the first train leaves the leaving block.

When the second train enters the leaving block, relay T is again dropped and'relays TPA, TPB and TPC' are again picked up. Relay IDSG is now dropped because its stick circuit is momentarily opened at back contact I55 of relay TPB before it is reclosed at front contact 245 of relay TPC as previously described. This extinguishes lamp 4L. Relay IR is again dropped because all of the contacts 28!] to 283 inclusive are open and relay IRP is dropped because of open front contact 285 of relay IR.

Relays IDSI and IDS3 are now picked up in response to the transfer from the No. 2 to the No. 1 group. Relay ID'SI is picked up over a circuit extending from front contact 24'I of relay TPC, conductor 248, front contact 231 of relay 2DSI, back contact I53 of relay IR, conductor I 54 and lower winding of relay IDSi, to Relay IDS3 is picked up (because relay 2DS3 is up) over a circuit extending from front contact 24? of relay TPC, conductor 248, front contact 238 of relay 2DS3, back contact 2H2 of relay IR, conductor M3 and lower winding of relay IDS3, to These two relays are stuck up over the previously described circuits including front contact 245 of relay TPC and front contacts I57 and 2M of relays iDSI and IDS3 respectively. Lamp ISL is now lighted by means of pyramid circuits for this lamp controlled by the No. 1 designation storage group of relays, which circuits are similar to those illustrated for the No. 2 group.

The dropping of relay IRP drops relays ZDSI and 2DS3 because of open front contact 288 of relay IRP. This extinguishes lamp I31.- of the No. 2 group.

Relay 2R is now dropped because front contacts 22B, 22I, 222 and 252 of the No. 2 group of storage relays are all open and relay ZRP is dropped because of open front contact 293 of relay 2R.

The dropping of relays 2DSI and 213.83 close a circuit for picking up relay IR which extends from front contact 23I of relay 2RP, back contacts 232 to 235 inclusive of the No. 2 group of relays, back contact 217 of relay IRP, conductor 2'I9, front contacts 280 and 282 in multiple of relays IDSI and IDS3, conductor 284 and lower winding of relay IR, to Relay IR completes its above described stick circuit and effects the picking up of relay IRP by closing front contact 285. This completes the second transfer operation, which transfers the designation from the second group to the first group.

When the second train leaves the leaving block, relay '1 is picked up and relays TPA, TPB and TPC are dropped as previously described. When the third train enters the leaving block relay T is again dropped and relays TPA, TPB and TPC are again picked up. Relays IDSI and IDS3 are dropped out when their stick circuits are opened at back contact I56 of relay TPB as previously described. Lamp ISL of the first group is now extinguished and relay SR is dropped because all of the contacts 233 to 283, inclusive, are opened and relay IRP is dropped because of open front contact 285 of relay IR.

When the third train leaves the leaving block, relay T is picked up and relays TPA, TPB and TPC are dropped as previously described. This places all apparatus and circuits in normal condition.

The purpose of relay PSP of Fig. 2A will now be explained. Ten trains and their classes can be stored on the ten groups of designation storage relays. With the ten groups loaded, the class of the eleventh train can be registered on the code receiver relay group, (illustrated in the upper left-hand portion of Fig. 2A) held and stepped up to group N0. 10 when this group is unloaded, by means of the circuit including front contact 2I5 of relay 3R, front contact 2H5 of relay IIJRP and the lowermost front contacts of the code receiver relays. When this operation is effected, a twelfth code is kept away from the code receiver by the picking up of relay PSP and the consequent opening of its back contacts 200 to 2133, inclusive. Relay PSP is picked up over a circuit extending from back contact 204 of relay SE conductor 235 and any on or more of front contacts 258, 219, 238 and 239 and the winding of relay PSP to Relay PSP is stuck up over a circuit closed at its front contact 2H, which stick circuit is effective until the code is unloaded from the code receiver and loaded onto the No. 10 designation storage group. This stick circuit of course includes any one or more of the above mentioned front contacts of the relays of the code receiver.

Extension Teceioer.The extension receiver is for the purpose of transferring the indication stored on the No. l designation storage group to another arrival point, when track relay T unloads this indication from the No. 1 group. Provision has been made for three successive transfers onto the No. 1A, 2A and 3A extension storage groups in response to three successive unloadings of the No. 1 storage group.

With the three designations above assumed, that is, train classes ltd, 4i and I3, successively indicated by the No. l designation group, it will be explained how these indications are successively, transferred to the three extension groups, stored and displayed until cleared out by the three trains entering the extension block. It will first be assumed that track switch repeater relay WPP is picked up in response to switch control lever SlVIL being in its normal position.

It will be recalled that code I24 was the first code stored in the No. 1 group, eifecting the picking up of relays IDSI, lDSZ and IDS l. When relay TPA picks up in response to the first train entering the leaving block as above described and before relay TPC picks up, a circuit is closed for picking up relays IADSI, IADS2 and IADS4 of the No. 1A extension storage group.

stick circuit for itself extending from back contact 3I3 of relay ATPB, front contact 3I4 and upper winding of relay IADSI, to

Relay IADS2 is picked up over a circuit including contacts 394 and 335 above described,

front contact 3I5 of relay IDSZ, front contact 3I6 of relay WPP back contact 3III of relay A3R, back contact 3I'l of relay AZRP, back contact 3I8 of relay AER, conductor 3I9, back contact 32B of relay AIRP, back contact 32I of relay AIR and lower winding of relay IADS2, to

Relay IADS2 closes a stick circuit for itself at its front contact 322.

Relay IADS4 is picked up over a similar circuit including front contacts 323 and 324 of relays IDSG and WPP back contacts 303, 325 and" 326 of relays A3R, AZRP and AER, conductor .321, back contacts 328 and 329 of relays AIRP and AIR and lower winding of relay IADS4, to Relay IADSG closes a stick circuit for itself at its front contact 330.

The picking up of relay TPA and the consequent opening of its back contact 33I prevents the picking up of relay AIRuntil sufficient time has elapsed for picking up the required relays of the No. 1A extension storage group, after which the closure of front contact 332 of relay TPC completes a circuit through back contacts 333, 334, 335 and 338 of relays A3RP, A3R, AZRP and AER, conductor 337, back contact 338 of relay AIRP and front contacts 339, 340 and 34F in multiple of relays IADSI, IADS2 and IADS I and lower winding of relay AIR, to Relay AIR completes a stick circuit for itself at its front contact 342 and at its front contact 343, it closes a pick-up circuit for relay AIRP.

When the second train enters the leaving block the operation of relays T TPA, TPB and TPC transfers the next indication, which is stored on the No. 1 designation storage group,

to the No. 2A extension storage group in a' manner which will be understood by analogy to the above described transfer operations. It will be obvious that the energization of the lower winding of relay 2ADS l is effected (since relay lDS l is assumed to be picked up) over a circuit including front contact 323 of relay H384 and the previously described circuit, which now extends through front contact 328 of relay AIRP to the lower winding of relay 2ADS4. Relay ZADSIl is stuck up because of closed front contacts 344 and 345. Relays AZR and AZRP operate in a manner similar to that described in connection with relays MR and AIRP for selecting the No 3A extension storage group of relays.

When the third train enters the leaving block, relays T TPA, TPB and TPC operate as before and, since it is assumed that relays IDSI and IDS3 are picked up, obvious circuits are completed through front contacts 30! and 341 of relay WPP and front contacts 308 and 348 of relay AERP for picking up relays 3ADSI and 3ADS3. These relays are stuck up over a circuit including front contact 349 of relay AZRP.

Relays A3R and A3RP are now operated in a manner similar to the operation of relays AIR. and AIRP and the circuits to the extension storage groups are opened at back contacts 300 to 303, inclusive.

It will be understood that the four relays of each extension storage group have pyramid contacts and circuits for selecting and energizing a group of lamps for each group, in a manner similar to that disclosed in connection with the No.

2 designation storage group of Fig. 2B.

The circuits including front contacts 350, 35!, "352 and 353 of the relays of the No. 1A extension storage group are shown leading off to the right, which indicates that additional storage groups may be provided if desired.

When the trains enter the extension block, relay 'I is dropped and relays ATPB and ATPC are picked up for effecting the transfer operation over a circuit controlled at contacts 354 and 355, which operation is similar to that described in connection with the transfer from one of the designation storage groups to the other and ,which need not be described in detail. It will be apparent that the transfer from the No. 3A extension storage group to the No. 2A extension storage group is effected over a circuit closed at front contact 356 of relay AIR and that the transfer from the No. 2A extension storage group to the No. 1A extension storage group is effected over a circuit closed at front contact 35 5 of relay A'I'PC.

When a train leaves the leaving block, relays TPA, TPB and TPC are dropped in sequence, the

stick circuit for the AIR, AZR and A3R relays is opened at front contact 357 of relay TPA, after which it is closed at back contact 358 of relay TPC. This effects the release of the highest numbered AR relay, in the event that its lower winding is not energized at this time due to one or more of the storage relays of the associated group being picked up and their front contacts, such as contacts 339, 340 and 3 1! of the No. 1A group, being closed.

The circuits including front contacts 359, 35E and 362 of relays A3RP, AZRP and AiRP are for a purpose similar to that described in connection with front contact 23! of relay ERP, that is, they provide pick-up circuits for picking up a lower numbered AR relay when its associated storage relay group has a code stored thereon, after the storage relays of the next higher numbered group have been dropped out.

From the above description it will be apparent that the dropping of relay WPP in response to the operation of lever SML to its reverse posi- 55' tion, may select circuits at back contacts 39?, 3|6, 341 and 324 leading to another extension group, such as a B extension group of storage relays. Since the operation of a B group will be the same as that described in connection with the A group, it is believed unnecessary to show the circuits or point out the detailed operation of such an additional group of storage relays.

Auxiliary perations.-An emergency cancelling button ECB is illustrated in Fig. 2C for the purpose of picking up relay TPB at the leaving end of the block by a manual operation, in order to clear out or cancel a storage designation independent of the entrance of a train into this block. This may be desirable if it becomes necessary, for any reason, to bring the system into step with the trains between the entering and the leaving .blocks, which might be occasioned by a train leaving or entering the track between the two ends of the bridge, thus resulting in the system getting out of step because such a train is not registered in and registered out as it should be.

An emergency suppression button ESB is provided, which efiects the picking up of relay ESR in response to a manual operation for preventing the opening of stick circuits for storage relays IDSI, IDSZ, IDS? and IDS-i by the closure of contact 201 of relay ESR in multiple with back contact I56 of relay TPB. The energization of relay ESR completes a stick circuit for itself at its front contact 206, and at its front contact 291 energy is applied to the stick circuit for the No. 1 designation storage group of relays.

More specifically, this suppression relay ESR if once picked up is stuck up through a stick circuit including back contact 245 of relay TBC, and will by reason of this back contact and front contact E53 of relay TPB remain'energized until relays TPB and TPC are sequentially .deenergized in that order. is first energized long enough to pick up relay TPC and is then deenergized long enough to open its own front contact 56. In other words, either occupancy followed by vacancy of the track circuit containing track relay T or depression and release of push button ECB is required to deenergize the suppression relay ESR. If the operator has therefore depressed push button ESB to render the suppression relay ESR effective he can cancel this action 'by depressing the push button ECB and then releasing it, but if the operator has picked up the suppressing relay ESR and then wishes to cancel the train description stored in storage relays lDSl, IDSZ, IDS3 and IDS-4 he will have to depress the push button ECB twice separated by a time interval. Also, if suppression relay ESR has been picked up manually, the first train that passes over the detector track circuit containing relay T will drop relay This can only occur if relay TPB ESR and the second train that passes over this track circuit will cause the train description to be cancelled by dropping of the storage relays. The operation of this relay ESR, therefore, prevents the unloading of the No. 1 designation storage group in response to a train entering the system is of the two-wire simplex type, that is,

messages are transmitted both ways over the two-wire line circuit, but only one way during each cycle of operations. The above description explained the transmission from the transmitter illustrated in Fig. 1A to the receiver illustrated in Fig. 2. With the system in its normal condition, transmission may be effected in the other direction over the line circuit and although the sending apparatus is not shown at the end of the system illustrated in Figs. 2 to 2D, inelusive; it will be understood thatthese sending circuits will be the same as illustrated in Fig. l and connected to the system at the bus Wire connections illustrated in Fig. 2, to which the legend same as at other station is applied. Similarly, a code receiver and any desired number of designation storage groups, as well as extension storage groups, may be provided at the end of the systemillustrated in Fig. 1A by connecting similar receiving circuits illustrated in Figs. 2 to 2D, inclusive, to the bus connections illustrated in the lower right-hand portion of Fig. 1A bearing the legend same as at other station.

Lock out-When a cycle of operations is ini- 7 tiated from the end of the system illustrated in Fig. 1A, relays C and PC are picked up for applying positive energy from line battery LB to the line circuit, which energy picks up the line relays and lockout relay LO at the receiving end in the manner previously described. The picking up of relay SB at the transmitting end and the consequent opening of its back contact 4 maintains the pick up circuit of relay LO at the transmitting end open, which pick up circuit was previously opened at back contact 3 of relay PC, so that relay L0 is ineifective during such a cycle.

Similarly, when transmission is effective the other way over the line circuit, relays C and P0 are picked up to apply positive energy from line battery LB to the line circuit which picks up the line relays and lockout relay LO of Fig. 1A. Front contact 9? of relay BB is closed to stick relay LO before its pick up circuit is opened at back contact 4. The picking up of relay 8B and the consequent opening of its back con-.

tact Hi3 opens the pick up circuit for relay L0 so that this relay will not be picked up during such a cycle.

The so called over-powering method of lockout is employed in the present system, that is, battery LB is of considerably higher potential than battery LB In the event of a simultaneous start at both ends of the system, relays C, PC, (3 and PC will be picked up at the same time. Since the potential of battery LB is higher than that of battery LB current will flow from the terminal of battery LB over the line circuit in such a direction that polar contact Sal of relay F and polar contact H5 of relay F will be positioned to the right. Relays FA and FA will be picked up, after which relays SA, SA SB and $13 will be picked up in the manner previously described.

The picking up of relay SA and the consequent opening of its back contact 39 opens the pick up circuit of relay C, but this relay is stuck up because contact 94 of relay F is in its right hand dotted position. The picking up of relay SA and the consequent opening of its back contact 299 opens the pick up circuit of relay C and since the stick circuit "for this relay is open (contact H5 of relay F being in its right hand dotted position and front contact 383 of relay S13 not yet closed), relay C will drop out.

Since relay C remains picked up, the circuit including its front contact 41] remains closed for energizing relay PC, but since relay C drops out the circuit including its front contact 35% is opened so that relay PC is dropped out. This removes battery LE from the line, connects lockout relay L0 in the line and maintains the line energized from battery LB of Fig. 1A. The system then steps through its cycle, with the location illustrated in Figs. 1 and 1A transmitting.

Incomplete cycle-A BZ relay is provided at each end of the system for opening up the line and sounding an alarm in the event of an incomplete cycle. The operation of relay BZ of Fig. 1A will be explained and this explanation will be typical of the operation of relay BZ of Fig. 2.

An incomplete cycle (which may be due to a trouble condition) will fail to pick up relay EX, then when relay SA drops and before relay SB drops a circuit is closed for picking up relay BZ which extends from back contact '7 of relay EX, front contact 6 of relay SB, back contact 5 of relay SA, and winding of relay BZ, to The closure of front contact 9 of relay BZ completes a circuit for the buzzer alarm and the closure of front contact 3 closes a stick circuit for relay B2. The opening of back contact 49 opens up the line and the opening of back con-- tact 37 opens up the start circuit. The operators at each end of the system now confer over a telephone line, or the like, and take steps to remedy the trouble, after which the BZ relays are released by the actuation of buttons RLB and RLB the latter not shown. 7

Having thus described a train describer system as one specific embodiment, it is to be understood that various modifications, adaptations and alterations may be applied to meet the requirements of practice withoutin any manner departing from the spirit or scope of the invention, except as limited by the appended claims.

What I claim is:

1. In combination; a plurality of train describer units; each unit comprising a plurality of storage relays which by being energized or deenergized describe the destination of a train, and a transfer relay having contacts in the in-put transfer pick-up circuits of said storage relays for allowing or not allowing a train description to be registered in such unit; of a two-position multiple contact switch connecting the out-put transfer wires of one unit to the in-put wires of one or the other of the two other units depending on its position, said two-position multiple contact switch by its position reflecting the position of a track switch over which said train moves; and means including a track relay associate with said track switch and one of said transfer relays for transferring a train destination stored in one of said units to one or the other of the other two of said train describer units depending on the position of said two-posi- 1 tion multiple contact switch.

2. In combination, three train describer units each including a first and second bank of storage relays each bank including a plurality of storage relays of which each bank will de--= scribe a train class by the condition of cnergization of its storage relays, a transferrelay between successive banks of storage relays of each describer for opening or leaving closed circuits for picking up storage relays of the first bank;

in accordance with the condition of energization of storage relays of the second bank, a set of double throw contacts one contact for each storage relay which contacts by their position reflect the position of a track switch over which.

said train moves for connecting front contacts of the first bank of storage relays of one describer unit to the storage relays of the second bank of one or the other of the remaining two describer units depending on the position assumed by said double throw contacts, a detector track relay associated with said track switch, and transfer circuits for transferring a train description from the first bank of storage relays of one describer to the storage relays of the sec-:

double throw two describers in any order depending upon the position assumed by said double throw contact at the time each particular transfer of description is made.

3. In combination; a track switch connecting a lead section to two diverging track sections; a detector track circuit associated with said track switch; three train describer units each comprising a plurality of storage relays, and a transfer relay one associated with each of said sections; a front contact on each of said storage relays; switch repeater contacts reflecting the position of said track switch; a pick-up circuit for each storage relay of the unit associated with one of said diverging sections including a front contact of the corresponding storage relay of the unit of the lead section, said switch repeater contacts closed when said lead section is connected by said track switch to that diverging section and also including back contacts of the transfer relay of the unit associated with that diverging section; a pick-up circuit for each storage relay of the unit associated with the other of said diverging sections including the same front contact of the corresponding storage relay of the lead section, said switch repeater contacts closed when said lead section is connected by said track switch to the other of said diverging sections and also including back contacts of the transfer relay of the unit associated with the other of said diverging sections; each of said pick-up circuits including contact mechanism closed only momentarily each time said detector track becomes occupied; whereby a train description is transferred from one describer unit to another in accordance with the route over which such described train moves.

4, In combination; a first train describer unit for describing a first'train; a second train describer unit for describing a second train and a third train describer unit for describing a third train; each of said units including a plurality of storage relays, a transfer relay and a transfer repeater relay controlled by a front contact of the transfer relay; said storage relays by their condition of energization defining the train stored therein; pick-up circuits for the storage relays of said second unit each including a front contact of the corresponding storage relay of the third unit, back contacts of the transfer relay of such second unit and front contacts of the transfer repeater relay of said first unit; a pick-up circuit for the transfer relay of said first unit including in multiple front contacts of the storage relays of saidfirst unit and in series back contacts of the storage relays of said second unit; and two stick circuits for the transfer relay of said first unit one including in multiple said front contacts of the storage relays of said first unit and its own stick contact and the other including in series back contacts of the transfer relayof said second and said third units and its own stick contact; whereby a train description cannot be registered in said first describer unit immediately after it is vacated without having first been registered in either the second or third of said train describer units. a

5. In a train describer; the combination with a train, describer unit including a plurality of storage relays, a transfer relay and a repeater transfer relay; a traffic relay which by its condition of energization manifests occupancy of a track circuit; a first repeater trafiic relay controlled by said traffic relay; a second repeater traffic relay controlled by said first repeater traffic relay; stick circuits for said storage relays each including a normally closed contact of said first repeater trafiic relay, whereby operation of said first repeater trafiic relay will deenergize said storage relays to cancel the train description stored therein; means including a normally open contact of said trafiic relay and a normally closed contact of said second repeater traffic relay for when actuated transferring the train description stored in said train describer to a subsequent train describer; and means for suppressing such cancellation including a manually controllable normally open contact in multiple with said normally closed contact of said first repeater traffic relay.

6. In a train describer; the combination with a train describer unit including a plurality of storage relays, a transfer relay and a repeater transfer relay; a traffic relay which by its condition of energization manifests occupancy of a track circuit; a first repeater trafiic relay controlled by said trafiic relay; a second repeater trafiic relay controlled by said first repeater traffic relay;-stick circuits for said storage relays each including a normally closed contact of said first repeater traffic relay, whereby operation of said first repeater traffic relay will deenergize said storage relays to cancel the train description stored therein; means including a normally open contact of said trafiic relay and a normally closed contact of said second repeater traffic relay for when actuated transferring the train description stored in said train describer to a subsequent train describer; a normally deenergized stick suppression relay which if energized suppresses such cancellation having a front contact connected in multiple with said normally closed contact of said repeater trafiic relay; a manually operable contact included in the pick-up circuit of said stick suppression relay; and a stick circuit for said stick suppression relay including its own stick contact and also including in multiple a normally closed contact of said second repeater traffic relay and a normally open contact of said first repeater trafiic relay; whereby the actuation of said trafiic relays in response to the entrance of a first train upon a track circuit causes deenergization of said stick suppression relay and the second actuation of said trafiic relays in response to the entrance of a second train upon such track circuit causes cancellation of a train description to take place.

'7. In combination, two stations connected by a pair of line wires, a source of current at each station, a line relay at each station included in series with one of said line wires, a lock relay at each station, contacts at each station for nor mally connecting said line relays and said lock relays in series which contacts for a particular station if actuated disconnect the lock relay at that station from the line wires and connect the source of current at that station in series in said line wires, a contact on each lock relay effective to prevent the source of current at its associated station being connected to said line Wires when such lock relay is energized, and indicating means controlled by said line relays.

8. In combination; two line wires connecting two spaced stations, a source of current at each station; a polar line relay at each station 'included in series in one of said line wires; a lock relay at each station; contacts at each station for normally connecting said polar line relays and said lock-out relays in series with said line 

